JP2015531996A - Method for depositing a metal film having oxygen vacancies - Google Patents

Abstract

A method is described for depositing an oxygen deficient metal film having a predetermined oxygen deficiency on a substrate by a chemical reaction of at least one precursor. An exemplary method is to expose a substrate to a metal reactive gas containing metal and an oxygen reactive gas containing oxygen during a metal oxide deposition cycle to form a layer containing the metal oxide on the substrate, oxygen deficiency During the deposition cycle, the substrate is exposed to a metal reactive gas containing metal and an additional reactive gas not containing oxygen, and a second layer of at least one of metal nitride and mixed metal during the second cycle. On the substrate, the second layer is deficient in oxygen compared to the layer containing the metal oxide, and repeats the metal oxide deposition cycle and the oxygen deficiency deposition cycle. Forming an oxygen-deficient film having defects. [Selection] Figure 1

Description

  Aspects of the invention relate to a method for depositing a metal film having an oxygen deficiency.

  The deposition of thin films on the substrate surface is an important process in various industries, including semiconductor processing, diffusion barrier coatings, dielectrics for magnetic read / write heads, and random access memory. In contrast to volatile memories such as DRAM memory modules, resistance change memory ("ReRAM" or "RRAM") is conventional because of its simple structure, long retention time, fast switching speed, and high scalability. There has been much interest as one of the possible candidates for future non-volatile memory devices that can replace flash memory. Metal oxide films containing transition metals are used in semiconductor applications, including high dielectric gate dielectric films, active materials for ferroelectric memories, thin film battery cathodes, materials in silicon-based light emitting devices, and memory cells It is done. RRAM is an emerging memory type that relies on an oxygen filament in a metal oxide film to adjust the resistance of the memory cell. Metal oxides with oxygen vacancies are desirable for the operation of RRAM cells. However, the ability to control the specific composition of the metal oxide deposition layer can be limited. Many metal-oxygen condensed phase systems use metal oxides that are stable at various oxidation potentials and are known to have well-defined stoichiometric phases. For these materials, it is generally possible to consistently obtain the desired metal oxide once the oxidation potential threshold is exceeded and equilibrium is reached. However, for applications where a metal oxide film with oxygen vacancies is desired, once the stoichiometric deposition occurs by physical vapor deposition (PVD) or chemical vapor deposition (CVD), some oxygen will be removed. Processes such as “scavenging” or “gettering” to absorb have been used.

  PVD has the limitation of being a non-conformal deposition method and has problems with scalability to a three-dimensional memory architecture. Since atomic layer deposition (ALD) is by definition a self-stopping and saturating process, it is virtually impossible to deposit a metal oxide film with oxygen vacancies using ALD, a variant of CVD. there were. Therefore, there is a need for CVD and ALD processes that can better control the oxygen level in order to produce a transition metal oxide thin film having a composition with oxygen vacancies on the substrate surface. This requirement is particularly critical in the field of depositing non-stoichiometric metal oxides such as transition metal oxides.

In RRAM, oxygen vacancies are required to carry charge through the dielectric layer in order to carry electrical signals between the top and bottom electrodes. Therefore, the metal ratio of oxygen in the metal oxide MO _x (M: O) can be controlled, desirable.

  One aspect of the present invention relates to a method of depositing an oxygen deficient metal composite film having a predetermined oxygen deficiency comprising at least two layers on a substrate by a chemical reaction of at least one precursor, the method comprising: Exposing the substrate to a metal reactive gas comprising metal and an oxygen reactive gas comprising oxygen during the metal oxide deposition cycle to form a layer containing the metal oxide, during the oxygen deficient deposition cycle Exposing the substrate to a reaction gas including a reaction gas, and optionally, a reaction gas not containing oxygen, a metal, a metal nitride, a metal carbon nitride, a metal carbide, a metal oxynitride, a metal oxygen carbon nitride, a metal Forming an oxygen deficient layer selected from one or more of a silicon compound, a metal nitride silicon compound (MSiN), a metal silicate, a metal nitride metal silicate (MSSiON), and combinations thereof The oxygen-deficient layer has an oxygen-deficient film having a predetermined oxygen deficiency by repeating the metal oxide deposition cycle and the oxygen-deficient deposition cycle that oxygen is deficient compared with the layer containing a metal oxide. The deposition method is selected from chemical vapor deposition and atomic layer deposition or a combination thereof.

A second aspect of the present invention relates to a method of depositing an oxygen deficient metal film having a predetermined oxygen deficiency on a substrate, the method comprising: (a) placing the substrate in a processing chamber; (b) (i ) Flowing HfCl ₄ gas over at least a portion of the substrate in the chamber under conditions that form a partial monolayer comprising hafnium terminated in chlorine on the substrate; (ii) flowing a purge gas; (iii) Performing a deposition process comprising flowing water vapor to the substrate in the chamber and (iv) flowing a purge gas under conditions to form a partial monolayer comprising hafnium oxide on the substrate; (c) ( i) under conditions that form a partial monolayer containing hafnium are terminated by chlorine, flowing a HfCl ₄ gas to at least a portion of the substrate in the chamber, flowing a (ii) a purge gas, under conditions that form a partial monolayer comprising iii) HfN, flowing a NH ₃ into the substrate in the chamber, and (iv) flowing a purge gas, to perform the second deposition process including, as well as ( d) repeating (b) and (c), wherein the deposition process is selected from chemical vapor deposition and atomic layer deposition or a combination thereof.

  A third aspect of the present invention relates to a method for depositing an oxygen deficient metal film having a predetermined oxygen deficiency on a substrate, the substrate comprising TiN. The method includes (i) first deposition comprising flowing a Hf precursor to at least a portion of the substrate in the chamber and flowing a purge gas under conditions that form a partial monolayer comprising hafnium on the substrate. Performing a process, flowing a Hf precursor to at least a portion of the substrate in the chamber, flowing a purge gas, and forming a partial monolayer comprising hafnium oxide under conditions to form a partial monolayer comprising hafnium Performing a second deposition process comprising flowing water vapor to a substrate in the chamber and flowing a purge gas under conditions forming above, and repeating the process, the deposition process comprising: Selected from chemical vapor deposition and atomic layer deposition or a combination thereof.

2 illustrates an exemplary embodiment of a composite membrane stack. Fig. 4 illustrates an alternative embodiment of a composite membrane stack.

  Before describing some exemplary embodiments of the present invention, it is to be understood that the present invention is not limited to the details of construction or process steps set forth in the description that follows. The invention is capable of other embodiments and of being practiced or carried out in various ways.

  In the semiconductor industry, in particular, miniaturization requires atomic level control of thin film deposition to produce conformal coatings on high aspect structures. One method for thin film deposition is chemical vapor deposition (CVD) in which vapor phase chemical precursor molecules and reactive gases react on and / or above a temperature controlled surface to form a thin film. ). The reactive species, energy, chemical feed rate, substrate temperature and the substrate itself contribute to determining the film properties. In a typical CVD process, the reactants are introduced into the reactor in the gas phase and activated by heat, plasma, or other means. The reactive species is then adsorbed onto the substrate surface, where it can undergo a chemical reaction or react with other incoming species to form a solid film. Reaction byproducts are desorbed from the substrate surface and removed or purged from the reactor.

  One variation of chemical vapor deposition for thin film deposition is atomic layer deposition (ALD), which is a continuous layer to form precise thickness layers controlled at the angstrom or single layer level. Self-stopping surface reactions are used. Most ALD processes are based on binary reaction sequences that deposit binary compound films. Since each of the two surface reactions occurs sequentially and they are self-stopping, the thin film can be deposited with atomic level control. Since the surface reaction is continuous, the two gas phase reactants are not in contact, limiting the possible gas phase reactions that can form and deposit particles. The self-stopping nature of the surface reaction also allows the reaction to reach completion during the entire reaction cycle, resulting in a continuous, pinhole free film.

  As used herein and in the appended claims, the term “purge” is used to mean any process in which the contents of a system are removed. Purging removes the contents (eg, gas reactant) by replacing it with another gas (eg, inert gas) or introduces a vacuum (or partial vacuum) into the system. It can mean that it is removed by.

  According to one or more embodiments, the present invention relates to a method of depositing a metal film having oxygen vacancies by a chemical reaction. A method, also referred to as a process, continues a substrate or a portion of a substrate into various deposition gases containing chemical precursors or reactants including a metal reactant gas, an oxygen reactant gas, a metal reactant gas and an additional reactant gas. Exposure. Purge gas can be flowed between exposures. In one cycle, the metal reactant gas and the oxygen reactant gas form at least a partial layer of metal oxide on the substrate during the first deposition process. In another cycle, the substrate is also continuously exposed to the metal reactant gas and the additional reactant gas. The metal reactive gas and the additional reactive gas form at least a partial layer of metal nitride on the substrate during the second deposition process. The first and second deposition processes are repeated in succession to form a mixed metal oxide / metal nitride or mixed metal film having the desired thickness. The first deposition process can be repeated multiple times before the second deposition process, the second deposition process can be repeated multiple times before the first deposition process, and either process first One skilled in the art will understand that this can also be done.

  According to one or more embodiments, the oxygen content of the film can be controlled by changing the thickness or ratio of the number of metal oxide and metal nitride layers. For example, to provide a greater amount of metal nitride layer than a metal oxide, thereby adjusting the oxygen content of the entire film formed by the process described herein, a plurality of metal nitrides The layers can be deposited in a ratio of 2: 1, 3: 1, 4: 1, 5: 1, 10: 1, 15: 1, and 20: 1 or more to the metal oxide layer.

In certain embodiments, the metal reactant gas used in both cycles can include any suitable metal-containing gas known to those skilled in the art. The metal can be the same or different in each cycle. Suitable metal species include Hf, Sr, Ni, Ti, Al, Zr, Cu, In-Zn, and PrCaMnO. In other embodiments, suitable metal species include SrTi, Cr—SrZr, PrCaMn, SrLaTi, LaSrFe, LaSrCo, and (Ba, Sr) Ti. In certain embodiments, the substrate is exposed to an oxygen reactive gas comprising oxygen species or oxidants. Suitable oxidants include, but are not limited to, H ₂ O, H ₂ O ₂ , O ₂ , O ₃ , N ₂ O, NO, NO _x , nitrates, alcohols, carboxylic acids, CO, CO ₂ , and HCOH. . Specifically, in some embodiments, the oxidant includes water. The substrate is also exposed to an additional reactive gas that is oxygen free or oxygen deficient. In certain embodiments, suitable oxygen deficient gases can include nitrogen, ammonia, alane, aluminum hydrocarbons, and the like. In certain embodiments, the additional reaction gas comprises one of alane, trimethylaluminum, triethylaluminum, dimethylaluminum hydride, dimethylethylamine alane, triethylamine alane, trimethylamine alane, and methylpyrrolidine alane. In certain embodiments, the method of the present invention forms a layer containing a metal oxide on a substrate during a metal oxide deposition cycle, and a metal nitride and mixed metal during a second cycle. At least one oxygen deficient layer is formed on the substrate, and the oxygen deficient layer is deficient in oxygen compared to the layer containing the metal oxide. Specifically, the method includes repeating a metal oxide deposition cycle and an oxygen deficiency deposition cycle to form an oxygen deficiency film having a predetermined oxygen deficiency.

The list of suitable metal oxide films contemplated by the present invention includes, but is not limited to, HfO ₂ , Al ₂ O ₃ , ZrO ₂ , TiO ₂ , NiO, Cu: MnO _x , Cu _x O, Cu: MoO _x , In—Zn—O, SrTiO ₃ , Cr—SrZrO ₃ , PrCaMnO ₃ , SrLaTiO ₃ , LaSrFeO ₃ , LaSrCoO ₃ , and (Ba, Sr) TiO ₃ are included. [Other? ]

The list of metal films with suitable oxygen vacancies anticipated by the present invention is not limited, but includes HfN, HfTiO, HfAl, NiN, TiN, PCMO, Al ₂ O, ZrO, TiO, Cu: MnO, Cu _x N, Cu: MoO, In-Zn-N, SrTiO, Cr-SrZrO, PrCaMnO, SrLaTiO, LaSrFeO, LaSrCoO, and (Ba, Sr) TiO are included.

In a detailed embodiment, the list of composite films contemplated by the present invention includes, but is not limited to, HfO ₂ / HfN, HfO ₂ / HfTiO, HfO ₂ / HfAl, Al ₂ O ₃ / Al ₂ O, ZrO ₂ / ZrO, TiO ₂ / TiO, NiO / NiN, Cu: MnO _x / Cu: MnO, Cu _x O / Cu _x N, Cu: MoO _x / Cu: MoO, ln—Zn—O / ln—Zn—N, SrTiO _{3 / SrTiO, Cr-SrZrO 3} / Cr-SrZrO, PrCaMnO 3 / PrCaMnO, SrLaTiO 3 / SrLaTiO, LaSrFeO 3 / LaSrFeO, LaSrCoO 3 / LaSrCoO, (Ba, Sr) TiO 3 / (Ba, Sr) TiO, HFO2 / TiN and combinations thereof.

In certain embodiments, the method includes placing the substrate in a processing chamber and forming a layer, eg, a TiN layer, on the substrate. Thereafter, flowing HfCl ₄ gas through at least a portion of the substrate in the chamber and subsequently flowing purge gas into the chamber under conditions that form a partial monolayer comprising chlorine-terminated hafnium. An oxygen deficient deposition cycle is performed. This may be followed by flowing NH ₃ to the substrate in the chamber followed by a purge gas under conditions that form a partial monolayer containing HfN. As an alternative, only HfCl ₄ gas is flowed during the oxygen deficiency deposition cycle to form an oxygen deficiency layer on the TiN layer. Then, HfCl ₄ gas is flowed through at least a portion of the substrate in the chamber, followed by purging gas into the chamber under conditions that form a partial monolayer comprising chlorine-terminated hafnium on the substrate. A metal oxide deposition cycle is performed. Then, under conditions that form a partial monolayer comprising hafnium oxide on the Hf layer on the substrate, water vapor may be flowed to the substrate in the chamber followed by a purge gas into the chamber.

This is followed by flowing HfCl ₄ gas through at least a portion of the substrate within the chamber and subsequently flowing purge gas into the chamber under conditions that form a partial monolayer comprising chlorine-terminated hafnium. A second deposition process can be performed. Thereafter, NH ₃ may be flowed to the substrate in the chamber, followed by a purge gas under conditions that form a partial monolayer containing HfN. The first deposition and the second deposition are then repeated until the oxygen deficient metal film reaches the desired thickness.

  During the purge, an inert gas is typically introduced into the processing chamber to purge the reaction zone or otherwise remove any residual reactive compounds or byproducts from the reaction zone. Alternatively, the purge gas may flow continuously throughout the deposition process so that only the purge gas flows during the time delay between reaction gas and reaction gas processing.

1 and 2 illustrate an exemplary embodiment of a composite film stack that can be formed according to embodiments of the present invention. The embodiments shown in FIGS. 1 and 2 are not limiting, and many other configurations can be provided by alternative embodiments. In FIG. 1 and FIG. 2, an example of a film stack is shown using a TiN layer and an Hf-containing layer. In FIG. 1, a TiN layer is formed on the substrate, and an oxygen deficient deposition cycle forms an Hf-containing layer on the TiN layer. A metal oxide deposition cycle then forms a HfO ₂ layer on the Hf layer. Thereafter, another Hf-containing layer is formed in the composite film stack in an oxygen deficient deposition cycle. A TiN layer is then formed on the composite film stack. FIG. 2 shows a deformation of a film stack with a TiN layer having alternating layers of Hf-containing and HfO ₂ formed during an oxygen deficient deposition cycle and an oxygen-containing deposition cycle, respectively. The film stack is completed with a TiN layer in the figure.

It should be noted that the Hf-containing layer, or “oxygen absorber”, need not be deposited via a reaction between HfCl ₄ and a reactive gas such as NH ₃ to form HfN. is there. In some embodiments, it is simply formed by thermal decomposition of the Hf precursor (only one or more Hf precursor pulses) under vacuum or under an inert atmosphere (with N ₂ purge gas). Can be done. Since HfCl ₄ has high thermal stability and does not decompose in the normal ALD process temperature range of 250-300 ° C., the organometallic (MO) precursors listed in claim 8 are for HfCl Compared to ₄ , it may be more appropriate. The thermal decomposition of the MO source usually results in the formation of a “Hf (C) _x (N) _y (O) _z ” (ie, having oxygen vacancies) film, depending on the precursor used.

In RRAM, oxygen vacancies are required to carry charge through the dielectric layer to carry electrical signals between the top and bottom electrodes. Typically, an RRAM cell can be composed of a TiN bottom electrode, a HfO ₂ or MO _x high dielectric constant layer, and a TiN top electrode. Certain embodiments of the invention are directed to a method of controlling or adjusting oxygen vacancies or oxygen concentration in the MO _x layer to minimize oxidation of the bottom and top electrodes. Specifically, the present invention is directed to a method for obtaining a composite film having a predetermined oxygen deficiency on a substrate. In one embodiment, the metal precursor or Hf precursor is pulsed into the chamber containing the TiN bottom electrode for one or more cycles. Thereafter, a purge gas is flowed. Exemplary Hf precursors can be, for example, Hf ₂ , HfCl ₄ , and the like. Thermal decomposition of the Hf precursor results in a thin layer of Hf containing film in contact with the TiN bottom electrode. The Hf-containing film can be, for example, Hf metal, HfC, HfN, HfCN, HfCNO, HF (Cl), or the like. In other embodiments, the Hf precursor can be HfLn, where Ln is not limited to amide, alkyl, hydride, halide (eg, Cl, Br, F), amidinate, guanidinate, Represents a ligand including cyclopentadienyl, beta diketonate, ketoiminate. In one embodiment, the Hf precursor is flowed in pulses for one or more pulse / purge cycles until the Hf-containing film reaches the desired thickness. An Hf precursor, such as HfCl ₄ gas, is flowed into at least a portion of the bottom electrode in the chamber under conditions that form a partial monolayer on the substrate containing chlorine-terminated hafnium, followed by The next deposition process, eg, atomic layer deposition or cycle, is performed by flowing a purge gas into the substrate. Thereafter, water vapor may be flowed to the substrate within the chamber followed by a purge gas into the chamber under conditions that form a partial monolayer comprising hafnium oxide on the substrate. Various metal precursors can be flowed into at least a portion of the bottom electrode in the chamber, followed by flowing an oxidant such as water vapor to provide the required high dielectric constant layer of metal oxide. It should be understood. It should then be understood that the deposition process can be repeated one, two or more times until the metal oxide high dielectric constant layer reaches the desired number or thickness. . Hf or metal precursor is then flowed during one or more pulse / purge cycles, after which the top TiN electrode is deposited.

In one embodiment, depositions of Hf or metal-containing layers are inserted before and after the high dielectric constant layer of HfO ₂ or metal oxide. In another embodiment, an Hf or metal-containing layer is inserted between the next HfO ₂ or metal oxide high dielectric constant layers. For example, alternating layers of Hf-containing layers / HfO ₂ layers can be deposited. In other examples, depending on the desired ratio of alternating layers, ie the ratio of Hf / HfO ₂ is, for example, from 1: 2 to about 1:20, or from about 2: 1 to about 20: 1. The Hf-containing layer can be deposited after every 2 cycles of HfO ₂ deposition, after every 3 cycles, after every 4 cycles, after every 5 cycles, and after every 10 cycles of HfO ₂ deposition, although it can be ranged. Specifically, the range of Hf / HfO ₂ can be, for example, from about 1: 5 to about 1:10. Without wishing to be bound by theory, insert metal or oxygen deficient layers alternating with layers of metal oxide high dielectric constant layers, and control the number and thickness of each such layer By doing so, the oxygen vacancies can be fine tuned or controlled, thereby not only minimizing oxidation of the bottom and top electrodes but also increasing the RRAM capacity. In one embodiment of the invention, the oxygen-deficient layer containing Hf or metal functions as an “oxygen absorber” for the high dielectric constant layer of HfO ₂ or metal oxide, and therefore in the metal oxide layer. To generate oxygen vacancies.

In one embodiment of the invention, the Hf or metal precursor may be the same for both the Hf or metal oxygen deficient layer deposition cycle and the HfO ₂ or metal oxide deposition cycle. Suitable precursors used in both metal deposition cycles and metal oxide deposition cycles include, but are not limited to, metal halides, metal nitrides, borides, sulfides, silicon compounds and pure metals.

In other embodiments, the Hf or metal precursor may be different for each individual deposition cycle. In one embodiment of the present invention, the method is performed continuously in situ without exposing the substrate to air. In other embodiments, each of the bottom and top electrodes, the metal or oxygen deficient layer, and the metal oxide layer can be grown starting from the same precursor. Suitable precursors useful for the growth of all three components, namely the bottom / top electrode, the metal layer, and the metal oxide layer include, but are not limited to, Ti (NR ₂ ) ₄ .

In general, in one or more embodiments, any of the layers described herein can be deposited by methods including, but not limited to, ALD, CVD, pulsed CVD, spray pyrolysis, and PVD. Certain embodiments of the present invention are directed to a method of obtaining an oxygen deficient composite film having a predetermined oxygen deficiency on a substrate. Specifically, composite films such as HfO ₂ / HfN and HfO ₂ / HfTiO and HfO ₂ / HfAl can be used for CVD, PVD, ALD, or plasma CVD (PE-CVD) and plasma ALD (PE-ALD). Made by vapor deposition. The processing chamber is configured to expose the substrate to a series of gases and / or plasmas during the deposition process.

  In some embodiments, the substrate is exposed to a metal reactant gas and an oxygen reactant gas. The exposure to these first and second gases can be substantially simultaneous, as in a CVD reaction, or can be continuous, as in an ALD reaction. As used herein and in the appended claims, the term “substantially simultaneously” means that two precursor gases are flowed into the chamber and react with each other and the substrate surface. means. It will be understood by those skilled in the art that there may be regions of the substrate that are exposed to only one precursor for a short time until the other precursor diffuses into that same region.

  In an atomic layer deposition type chamber, the substrate may be exposed to the first gas and the oxygen reactive gas in a process that is separated either spatially or temporally. Temporal ALD is a traditional process in which a metal reactive gas is flowed into the chamber and reacts with the surface. Prior to flowing the oxygen reactant gas, the metal reactant gas is purged from the chamber. In spatial ALD, both the first gas and the oxygen reactant gas are flowed into the chamber at the same time, but are spatially separated such that there is a region between the flows that prevents gas mixing. In spatial ALD, the substrate must move relative to the gas supply plate, or vice versa.

  The processing chamber or deposition chamber is in the range of about 0.01 Torr to about 80 Torr, such as about 0.1 Torr to about 10 Torr, more specifically about 0.5 Torr to about 2 Torr. The ALD process defines that it can be maintained at the same pressure. Also, according to one or more embodiments, the chamber or substrate may be less than about 600 ° C., such as in the range of about 200 ° C. to about 400 ° C., or less, and other implementations. In a form, it can be heated to a temperature in the range from about 50 ° C. to 100 ° C., such as in the range from about 70 ° C. to 90 ° C., for example in the range from about 70 ° C. to less than about 100 ° C. As will be appreciated by those skilled in the art, ALD reactions at low temperatures may benefit from the presence of a catalyst. Suitable catalysts include but are not limited to ammonia, pyridine and Lewis base.

  In some embodiments, one or more layers may be formed during a plasma atomic layer deposition (PEALD) process. In some processes, the use of plasma provides sufficient energy to raise the species to an excited state where surface reactions are advantageous and can occur. Introducing the plasma into the process can be continuous or pulsed. In some embodiments, a continuous pulse of precursor (or reactive gas) and plasma is used to process the layer. In some embodiments, the reagent can be ionized either locally (ie, within the processing region) or remotely (ie, outside the processing region). In some embodiments, remote ionization can occur upstream of the deposition chamber so that ions or other energetic or luminescent species are not in direct contact with the deposited film. In some PEALD processes, the plasma is generated outside the processing chamber, such as by a remote plasma generator system. The plasma may be generated by any suitable plasma generation process or technique known to those skilled in the art. For example, the plasma may be generated by one or more of a microwave (MW) frequency generator or a radio frequency (RF) generator. The frequency of the plasma can be adjusted depending on the particular reactive species being used. Suitable frequencies include but are not limited to 2 MHz, 13.56 MHz, 40 MHz, 60 MHz and 100 MHz. It should be noted that although a plasma may be used during the deposition process disclosed herein, a plasma may not be required. Indeed, other embodiments relate to deposition processes under very mild conditions without plasma.

  According to one or more embodiments, the substrate is treated before and / or after forming the layer. This processing can be performed in the same chamber or in one or more separate processing chambers. In some embodiments, the substrate is moved from the first chamber to another second chamber for further processing. The substrate can be moved directly from the first chamber to another processing chamber, or it can be moved from the first chamber to one or more transfer chambers and then moved to another desired processing chamber. Can be made. Thus, the processing apparatus can comprise a plurality of chambers in communication with the transfer station. This type of device may be called a “cluster tool” or a “cluster system”.

  Generally, a cluster tool is a modular system with multiple chambers that perform various functions including substrate center measurement and orientation, venting, annealing, deposition, and / or etching. According to one or more embodiments, the cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber can house a robot that can reciprocate substrates between multiple processing chambers and multiple load lock chambers. The transfer chamber is typically maintained in a vacuum condition and provides an intermediate stage for reciprocating the substrate from one chamber to another and / or to a load lock chamber located at the front end of the cluster tool. Two well-known cluster tools that can be adapted for the present invention are Centura® and Endura®, both of which are Santa Clara, Calif. Applied Materials, Inc. Is available from Details of one such staged vacuum substrate processing apparatus are disclosed in US Pat. No. 5,186,718, issued February 16, 1993, entitled “Staged-Vacuum Wafer Processing Apparatus and Method”, Tepman et al. ing. However, the exact arrangement and combination of the chambers can be varied for the purpose of performing certain steps of the process as described herein. Other processing chambers that can be used include, but are not limited to, periodic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etch, preclean, Includes chemical cleaning, heat treatments such as RTP, plasma nitridation, degassing, orientation, hydroxylation, and other substrate processing. By performing the process in a chamber on the cluster tool, surface contamination of the substrate with impurities in the air can be avoided without oxidizing prior to depositing the next film.

  According to one or more embodiments, the substrate is continuously under vacuum or load lock conditions and is not exposed to ambient air as it is moved from one chamber to the next. The transfer chamber is thus under vacuum and is “pumped down” under vacuum pressure. An inert gas may be present in the processing chamber or the transfer chamber. In some embodiments, after forming a silicon layer on the surface of the substrate, an inert gas is used as a purge gas to remove some or all of the reactants. According to one or more embodiments, a purge gas is injected at the outlet of the deposition chamber to prevent reactants from moving from the deposition chamber to the transfer chamber and / or additional processing chamber. Thus, the flow of inert gas forms a curtain at the exit of the chamber.

  The substrates can be processed in a single substrate deposition chamber, where a single substrate is loaded, processed, and unloaded before other substrates are processed. The substrates can also be processed in a continuous manner, such as a conveyor system, where a plurality of substrates are individually loaded into the first portion of the chamber and moved through the chamber, Unloaded from the second part of the chamber. The shape of the chamber and associated conveyor system can form a straight path or a curved path. Additionally, the processing chamber may be a carousel in which multiple substrates move around the central axis and are exposed to deposition, etch, annealing, cleaning, and other processes throughout the carousel path.

  During processing, the substrate can be heated or cooled. Such heating or cooling is accomplished by any suitable means including, but not limited to, changing the temperature of the substrate support and flowing a heated or cooled gas over the substrate surface. be able to. In some embodiments, the substrate support includes a heater / cooler that can be controlled to change the substrate temperature through conduction. In one or more embodiments, the gas being used (either a reactive gas or an inert gas) is heated or cooled to locally change the substrate temperature. In some embodiments, a heater / cooler is placed inside the chamber adjacent to the substrate surface to change the substrate temperature in convection.

  The substrate can also be stationary or rotated during processing. The rotating substrate can be rotated continuously or in discrete steps. For example, the substrate may be rotated during the entire process, or the substrate may be rotated by a small amount during exposure to various reactive or purge gases. Rotating the substrate (either continuously or stepwise) during processing can result in a more uniform deposition or etch, for example, by minimizing the effects of local variability in gas flow geometry. Can help make.

  Throughout this specification “one embodiment”, “some embodiments”, “one or more embodiments”, “one embodiment”, “one aspect”, “some aspects”, Reference to “one or more embodiments” and “one aspect” refers to a particular feature, structure, material, or characteristic described in connection with the embodiment is at least one implementation of the invention. Means included in the form. Accordingly, various places throughout the specification can be found in various places, “in one or more embodiments”, “in some embodiments”, “in one embodiment”, “in one embodiment”, “ The appearances of phrases such as “in accordance with one or more aspects”, “in one aspect” and the like do not necessarily refer to the same embodiment or aspect of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or aspects. The order of description of the above methods should not be considered limiting and the methods may use the operations described in a different order or with omissions or additions.

It should be understood that the above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such rights are given.

Claims (15)

A method of depositing an oxygen deficient metal composite film having a predetermined oxygen deficiency including at least two layers on a substrate by a chemical reaction of at least one precursor,
Exposing the substrate to a metal reactive gas comprising a metal and an oxygen reactive gas comprising oxygen during a metal oxide deposition cycle to form a layer containing the metal oxide;
During the oxygen deficiency deposition cycle, the substrate is exposed to a reaction gas containing a metal reaction gas and optionally a reaction gas not containing oxygen, and a metal, metal nitride, metal carbon nitride, metal carbide, metal oxygen Selected from one or more of nitride, metal oxygen carbon nitride, metal silicon compound, metal nitride silicon compound (MSiN), metal silicate, metal nitride metal silicate (MSSiON)), and combinations thereof Forming an oxygen deficient layer, wherein the oxygen deficient layer is deficient in oxygen compared to the layer containing the metal oxide, and the metal oxide deposition cycle and the step Repeating the oxygen deficiency deposition cycle to form the oxygen deficient film having the predetermined oxygen deficiency,
The deposition method is selected from chemical vapor deposition and atomic layer deposition or a combination thereof.   The method of claim 1, comprising an additional reactive gas, wherein the fourth reactive gas comprises one of nitrogen, argon, helium, ammonia, hydrogen, alane, hydrocarbons, and silane. The oxygen deficiency deposition cycle is first performed to deposit the oxygen deficiency layer directly on the substrate, the oxygen deficiency deposition cycle comprising Hf, Sr, Ni, Ti, Al, Zr, Cu, In, Zn Continuously exposing the substrate to a gas containing a metal selected from Pr, Ca, and Mn, and forming a second layer on the oxygen deficient layer;
And the metal oxide deposition cycle is performed on a reactive gas containing one or more metals selected from Hf, Sr, Ni, Ti, Al, Zr, Cu, In, Zn, Pr, Ca, and Mn. The method according to claim 1, comprising continuously exposing the substrate to form the layer containing a metal oxide on the oxygen deficient layer.   The metal reactive gas contains one or more metals selected from Sr, Ti, Cr, Zr, Pr, Ca, Mn, La, Fe, and Co, respectively. the method of.   5. The method according to claim 1, further comprising adjusting the oxygen deficiency in the composite film by repeating the oxygen deficiency deposition cycle and the metal oxide deposition cycle at least once.   6. The oxygen deficient layer is deposited first, then deposits the layer containing metal oxide, and then deposits a second oxygen deficient layer. The method described. The composite film is made of HfO ₂ / HfN, HfO ₂ / HfTiO, HfO ₂ / HfAl, Al ₂ O ₃ / Al ₂ O, ZrO ₂ / ZrO, TiO ₂ / TiO, NiO / NiN, Cu: MnO _x / Cu _{: MnO, Cu x O / Cu} x N, Cu: MoO x / Cu: MoO, ln-Zn-O / ln-Zn-N, SrTiO 3 / SrTiO, Cr-SrZrO 3 / Cr-SrZrO, PrCaMnO 3 / PrCaMnO , SrLaTiO ₃ / SrLaTiO, LaSrFeO ₃ / LaSrFeO, LaSrCoO ₃ / LaSrCoO, (Ba, Sr) TiO ₃ / (Ba, Sr) TiO, Hf (La) O _x , Hf (Ln) O _x And one or more selected from combinations thereof) The method according to.   The metal reactive gas is a metal halide, metal amide, metal hydride, metal alkyl (wherein alkyl includes C1-C8 hydrocarbon, cyclopentadienyl, alkyl-substituted cyclopentadienyl), metal alkoxide, metal The method of any one of claims 1 to 7, comprising at least one of beta diketonate, metal ketoiminate, metal amidinate, metal guanidinate, and mixtures thereof.   9. A method according to any one of claims 1 to 8, wherein the metal reactant comprises a metal halide.   The method according to any one of claims 1 to 9, wherein the oxygen reactive gas comprises oxygen and the additional reactive gas does not comprise oxygen. The metal reactive gas comprises a metal chloride and the oxygen reactive gas comprises H ₂ O, O ₂ , ozone, oxygen plasma, H ₂ O ₂ , NO, NO _x , and N ₂ O. The method according to any one of 10 above.   12. The metal reactive gas according to any one of claims 1 to 11, wherein the metal reactive gas comprises at least one of a metal amide and a metal chloride during the oxygen deficient deposition cycle and the additional reactive gas comprises nitrogen. The method described.   13. The method according to any one of claims 1 to 12, wherein the additional reaction gas comprises ammonia or one of alane and aluminum hydrocarbons, silane, borane. The second layer includes HfTiO, and the second cycle includes HfCl ₄ , Hf (NR 2) 4 (where R = C 1 -C 6 hydrocarbon), Hf (OR) 4, hafnium beta diketonate, Hafnium amidinate, hafnium guanidinate or its heteroleptic ligand-metal complex and Ti (OPr) ₄ , Ti (NR 2) 4 (where R = C 1 -C 6 hydrocarbon), TiCl 4, titanium beta 14. Exposing the substrate to one or more of a diketonate, titanium amidinate, titanium guanidinate, or a heteroleptic ligand-metal complex thereof. The method according to any one of the above. The second layer comprises HfAl, and the second cycle comprises one of HfCl ₄ and alane, trimethylaluminum, triethylaluminum, dimethylaluminum hydride, dimethylethylamine alane, triethylamine alane, trimethylamine alane and methylpyrrolidine alane. 16. A method according to any one of claims 1 to 15, comprising exposing the substrate to one or more.

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